When it comes to the pesky flea, ignorance is bliss

A flea under a microscope looks, at first glance, a bit like Wimpy, the celebrated moocher in the Popeye cartoon who used to say "I'd gladly pay you Tuesday for a hnmburger today. "Through the lens, the glossy, I amber freckle off flea comes into focus: it is a hog-backed round-bellied, no-neck sort of insect, dim-looking, with combs and palpi that droop down over its mouth like a mustache. The flea is of course also a moocher. Over 100 million years, fleas have evolved sometimes on bizarre lines, to find their victim, leap on board, slip deftly through feather or fur, and bite without being harrowed up by angry beak, finger, fang, or claw. The flea has made humans, along with a variety of other unfortunate birds and mammals, its hamburger.